Water-soluble electrically conducting polymers, their synthesis and use

ABSTRACT

Disclosed is a novel composition of matter comprising a polyacid and a polymer containing repeating units which contain one or more basic atoms. The complex is water-soluble and electrically conductive. The complex is useful in providing organic discharge layers for use in electronic applications and fabrications.

BACKGROUND OF THE INVENTION

The present invention relates to novel electrically conductive polymercomplexes, electrically conductive resists, uses thereof and structuresfabricated therewith. More particularly, this invention relates towater-soluble, electrically conductive substituted and unsubstitutedpolymer complexes and their use as, inter alia, electrical dischargelayers, resists, discharge layers for electron-beam lithography and SEM(scanning electron microscope) inspection, and as coatings (especiallyradiation-curable coatings), for electrostatic charge (ESC) andelectrostatic discharge (ESD) applications.

In electron-beam lithography using organic resists, which areinsulators, there can arise an accumulation of charge during the writingprocess due to the absence of an adequate conducting path for immediatebleed-off of the electrons. This charging can result in beam patterndisplacement deflection, loss of accuracy in pattern-to-pattern-overlay,or in extreme cases a catastrophic discharge of voltage.

Traditionally, suggestions to circumvent this problem have included theuse of a discharge layer in the form of a conductor below or above theresist coating. The layer could be in the form of thin evaporated orsputtered metal coatings, indium-tin oxide films, or amorphous carbonfilms produced by chemical vapor deposition processes. Althougheffective in some contexts, these methods are not universally idealsince the processes involved in their utilization tend to influencenegatively the performance of the resist, and in some cases aredifficult to remove.

It is also useful to provide materials that can alleviate electrostaticcharging (that is, the unwanted accumulation of static electricity whichbecomes capable of attracting unwanted airborne particles to e.g.cathode ray tube screens and electronic component carriers), andalleviate electrostatic discharge, in which static electricity issuddenly released in a discharge that can distort the performance ofelectronic devices and even damage or destroy electronic components. Amaterial that can facilitate the application and creation of suchmaterials would be useful.

While polyaniline as described in the literature might be considered apromising candidate to use to solve these needs, the practical use ofcurrently available polyaniline-based systems has been limited due tothe fact that solvents such as N-methyl pyrrolidinone are needed for theapplication and removal. These solvents are known to interfere with somesubstrate chemistries. In addition, they create interfacial problems andcan tend to dissolve certain substrates. Still other selectivepolyaniline-derived systems are soluble in more benign organic solvents;however, they are known to be difficult to remove once applied. It isalso useful to form a conducting resist which provides patterns ofconductive lines on a substrate. The steps involved in forming suchlines can include depositing a layer, exposing selected portions of thelayer to a given radiation (e.g., ultraviolet or visible light, electronbeam, X-ray, or ion beam) to create a solubility difference betweenexposed and unexposed portions, and then removing the more solubleportions so that only the desired pattern remains. This type oftechnique is often frustrated by the difficulty of removing the unwantedmaterial after it is developed.

The problem of charging in electron-beam methods arise because theresists are insulators. With a conducting resist, which is one aspect ofthe present invention, charging should not occur and a separatedischarge layer should not be needed.

Thus, there remains a need for a polymeric material which can be used inthe applications described herein, and which is easily applicable; ischemically inert with respect to the systems with which it is used; isenvironmentally benign, particularly in not requiring the use of organicsolvents which would volatilize into the atmosphere; and which isremovable when desired with minimal effort, with minimal harm to thesubstrate itself.

DESCRIPTION OF PRIOR ART

The preparation of polyaniline systems is described in Li et al.,"Soluble Polyaniline" in Synthetic Metals, 20 (1987), at pages 141-149.That article discloses that, even when the polymerization of the anilineis carried out in the presence of the polyacid polystyrene sulfonic acid(PSSA), the polymerization results in a precipitate from the aqueoussolution in which the aniline polymerization proceeds.

MacDiarmid et al., in "Polyaniline: A New Concept in ConductingPolymers", Synthetic Metals, 18 (1987), at pages 285-290, describepolyaniline and its protonated form, and indicate that the material iselectrically conductive.

U.S. Pat. No. 5,068,060 relates to the synthesis of poly(heterocyclicvinylenes) as electrically conductive materials. According to thedisclosure, the backbone of the polymer is altered to impart desiredproperties, and solubility is exhibited only in an undoped precursorform. U.S. Pat. Nos. 4,929,389 and 4,880,508 relate to the synthesis ofwater soluble conductive polymers, in which the moiety responsible forwater solubility is incorporated into the backbone of the polymer. Bycontrast, in the present invention the final product exhibits both watersolubility and electrical conductivity, and does so without requiringalteration of the polymer backbone.

U.S. Pat. No. 4,375,427 relates to the synthesis of thermoplastic-typepolymers that can be doped to be made conductive. However, the disclosedmaterials are not water soluble, and are synthesized by condensationreactions rather than oxidation reactions.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention resides in a water-solubleelectrically conductive composition of matter comprising a polyacid anda polymer comprising at least one conjugated region composed ofrepeating units incorporating a conjugated basic atom. A preferredexample of such a repeating monomeric unit is aniline or a substitutedaniline, which incorporates a nitrogen atom in that the nitrogen canparticipate in the conjugation in the polymer.

Another aspect of the present invention comprises solutions, inparticular aqueous solutions, of such compositions of matter.

Another aspect of the present invention comprises a process for forminga water-soluble, electrically conductive composition of mattercomprising a polyacid and a polymer, such as polyaniline, comprising atleast one conjugated region composed of monomeric units incorporating aconjugated basic atom. The process comprises forming a solution of saidpolyacid and the corresponding monomer, wherein the number of acidgroups in the polyacid exceeds the number of protonatable basic atoms inthe polymer to be formed (it being understood that the polymer willinclude basic atoms that are not protonatable), and polymerizing themonomer while controlling the rate of initiation and the rate ofpropagation of said polymerization such that the polymerization formssaid water-soluble composition of matter.

Further aspects of the invention includes compositions of matter whichare water-soluble and electrically conductive as described herein andwhich are crosslinkable upon exposure to electromagnetic radiation toform water-insoluble conductive products; structures having such acomposition of matter disposed thereon; processes of using suchcompositions of matter to make electrically conductive layers and films;and the products formed by such cross-linking, such as conductingresists.

Yet another aspect of the present invention is a structure, comprising asubstrate on which is disposed said water-soluble electricallyconductive composition of matter. Such structures include dielectricmaterials; said composition of matter is useful as a conductive electronbeam resist, optical resist, X-ray resist, and electrostatic dischargelayer.

A further aspect of the present invention comprises a method ofdisposing said water-soluble, electrically conductive composition ofmatter on a surface as e.g. a conductive resist or an electrostaticdischarge layer.

DETAILED DESCRIPTION OF THE INVENTION

Without being bound by any particular theory of the present invention,the observed behavior of the composition of matter which is one aspectof the present invention is consistent with the belief that the polyacidand the polymer which comprise the composition of matter are in mutualassociation with each other. The association is believed to be moreionic in character than covalent. Thus, while the composition of matteris described herein as comprising polyacid and polymer, as described, itwill be recognized that in situ the composition of matter can also beunderstood as comprising the polymer in which basic atoms, or even allbasic atoms, are protonated by hydrogen ions from the acidic groups ofthe polyacid. However, it will be understood that the precise nature ofthe association is not controlling.

Different regions of a given polyacid molecule may be associated withbasic atoms on distinct polymer molecules, without departing from theinvention whose noteworthy aspects include the water solubility andelectrical conductivity of the composition of matter.

The polyacid component of the present invention can, in its broadestaspect, comprise any organic polymer at least some, or all, of whoserepeating units include an acidic moiety. The acidic moiety can becarboxylic, i.e. --COOH, or can be another group such as a phosphonicacid group, a phosphoric acid group, a boric acid group (i.e. --BO₂ H),a sulfuric acid group, or a sulfonic acid group. The acidic group can bependant directly from the polymer backbone, or can be a substituent onanother group which is itself pendant from the polymer backbone.

The preferred polyacids suitable for use in the present invention arewater-soluble at the concentrations described herein in which thepreparation of the complex of the present invention is carried out.

Preferred polyacids have polymer backbones which are vinylic, that is,composed of repeating units of the generalized formula --(CH₂ CHX)--,wherein X is an acid group or is a substituent which is substituted withan acid group.

Preferred examples of polyacids include poly(styrene sulfonic acid),poly(acrylic acid), poly(methacrylic acid), poly(vinyl sulfonic acid),poly(vinyl sulfuric acid), poly(vinyl boric acid), poly(styrene boricacid), poly(vinyl phosphoric acid), and poly(styrene phosphoric acid).The preferred polyacid is poly(styrene sulfonic acid), referred to atpoints herein as PSSA.

It should also be recognized that polyacids suitable for the practice ofthe present invention may comprise copolymers some repeating units ofwhich contain pendant acidic groups as described hereinabove and otherrepeating units of which do not, provided that such copolymericpolyacids exhibit the desired solubility in water. Such copolymers canbe block copolymers, or copolymers in which acidic and non-acidicmonomeric units are interspersed.

The polymer component of the compositions of matter of the presentinvention comprises one or more conjugated regions composed of monomericunits incorporating a conjugated basic atom. By "basic atom" is meant anatom that can form the positive part of an ionic couple by electrondonation with the anionic moiety of the deprotonated acid group of thepolyacid. The preferred basic atom is nitrogen. Other basic atomsinclude sulfur. The polymer is preferably of the type which can beprepared by oxidation-type polymerization as distinguished fromcondensation polymerization.

The polymer is characterized in that at least one region thereof isconjugated as a whole and is composed of monomeric units each of whichincorporates a basic atom which is conjugated. Referring for simplicityto the well-known means of depicting the structure of a molecule usingconventional atomic symbols and single and double bonds, by "conjugated"is meant as to a region that the structure of the region can be depictedin that means in more than one way (the actual structure in siturepresenting an average of all such depictions), and as to an atom thatthere is more than one way to depict the bonds connecting that atom toadjacent atoms. It is preferred, though not necessary, to extend theconjugation over the full extent of the polymer molecule. In theconjugated system an electron is essentially delocalized over the entireregion of conjugated bonds. These electrons are more loosely bound andare available for electrical conduction. It is only necessary tosufficiently extend the conjugated region of an individual polymermolecule so that when the conjugated region of an individual molecule isadjacent to a part of the conjugated region of an adjacent molecule, andan electric field is applied, an electron can flow along an individualmolecule and hop from one molecule to an adjacent molecule in a regionwhere the conjugated regions of the adjacent molecules overlap.

Examples of polymers incorporating the foregoing characteristics includepolymers containing conjugated regions, or composed entirely, ofrepeating units which are substituted or unsubstituted aniline,thiophene, pyrrole, and/or phenyl mercaptan (C₆ H₅ SH). Preferredexamples of these include polyaniline, polythiophene, polypyrrole,poly(p-phenylene sulfide), and copolymers of these polymers. Polymersuseful in the present invention also include polymers of any of thecorresponding monomers which are ring-substituted with one or morestraight or branched alkyl, alkoxy, or alkoxyalkyl groups, which cancontain from 1 up to about 30 carbon atoms and preferably 1 to 6 carbonatoms, particularly where such substituents are cross-linkable with eachother as described in more detail hereinbelow. It will also berecognized that polymers incorporated within the compositions of matterof the present invention may also be copolymers of any one or more ofsuch monomers with other comonomers having ethylenic unsaturation,including but not limited to ethylene, propylene, vinyl chloride,styrene, vinyl alcohol, vinyl acetate. In such cases, as describedabove, the conjugated region or regions containing the basic monomericunits should comprise a block sufficiently long as to render thecomposition of matter conductive.

The preferred polymers within the compositions of matter of the presentinvention are polyaniline, poly{alkoxyalkyl aniline),poly(alkoxyaniline), and poly(alkylaniline) wherein the alkoxy and alkylgroups contain 1 to 6 carbon atoms and more preferably about 2 carbonatoms.

The compositions of matter of the present invention are uniquelycharacterized in that they exhibit solubility in water, and form inpolar solvents solutions that remain stable even over protracted periodsof time. These compositions of matter are also recoverable from suchsolutions as solids, which are conductive and which can be redissolvedinto water. In addition, the compositions of matter of the presentinvention exhibit significant electrical conductivity in the solid stateas well as in solution in polar solvents.

The molecular weight of the compositions of matter of the presentinvention can be virtually any that the practitioner may desire,depending on the desired application. Thus, the compositions of mattermay have a molecular weight on the order of 1,000 to a molecular weighton the order of 100,000, but more preferably on the order of 10,000 to25,000, e.g. about 20,000.

The preparation of the compositions of matter in accordance with thepresent invention calls for polyacid, the desired monomer (orcomonomers), a suitable solvent, and an effective amount of an initiatorfor the desired polymerization of the monomer(s).

The polyacid can be any polyacid meeting the characteristics describedabove. The monomer is selected with regard to the desired final polymer;in the preferred embodiment, the polyacid is PSSA and the monomer isaniline. For applications intended to produce a cross-linked product,the preferred monomers are o-ethylaniline or o-ethoxyaniline.

The solvent is a polar liquid in which the polyacid, monomer and finalcomplex are soluble. Water is the preferred solvent; the solvent mayalso be an alkanol or a water/alkanol mixture.

The initiator is any material capable of initiating the oxidationpolymerization of the monomer(s) present. The preferred initiator isammonium persulfate, particularly when the monomer to be polymerized isan aniline. Other useful initiators include hydrogen peroxide, AIBN,iron trichloride, potassium permanganate, and others which will bereadily apparent to those of ordinary skill in this art.

The amounts of polyacid and monomer need to be selected such that thenumber of acidic groups in the polyacid present in the reaction mixtureexceeds the numbers of the basic atoms present in the quantity ofmonomer provided to the reaction mixture. Preferably, the finalcomposition of matter that is obtained will have an excess of acidicmoieties not associated with basic atoms in the polymer, therebycontributing to the water solubility of the composition of matter. Thus,it will be understood that as the ratio of acidic groups in the polyacidto basic atoms in the monomer reaction mixture increases, the watersolubility of the composition of matter also increases. It ispermissible that some of the acidic moieties on the polyacid areconverted to salts with a cation (such as an alkali metal or ammonium),before or after the polymerization, so long as sufficient acidicmoieties are present that protonate the protonatable basic atoms of thepolymer so as to provide the desired solubility and conductivity.

It has been discovered that if the polymerization of the monomer ormonomers in the presence of the polyacid is carried out under carefullycontrolled conditions, the desired water-soluble, electricallyconductive composition of matter is formed and remains in solution untilremoval thereof from solution is desired. The practitioner will readilybe able to confirm that the composition of matter of the presentinvention has been formed because the product of the polymerizationdescribed herein is a stable solution. By contrast, polymerizations thatfail to produce the desired water-soluble soluble composition of matterare readily distinguished by the formation of a precipitate or aninsoluble gel (which is the result reported in the literature uponprevious attempts at polymerization of such monomers in the presence ofacids such as PSSA).

In general, the careful control of the polymerization is characterizedby control of the rate of initiation of the polymerization, and of therate of propagation of the polymer. This control can be provided, inturn, by controlling the temperature and adjusting the concentration ofthe polyacid, the monomer, and the initiator to levels below thoselevels at which the polymerization forms a precipitate. As indicated thepractitioner will readily be able to determine for any particularcombination of polyacid, monomer and initiator those concentrationsthereof at which the polymerization will lead to the desired formationof the water-soluble, electrically conductive composition of matter inaccordance with the present invention. The examples which follow willprovide further guidance to the practitioner as to those concentrationconditions which permit formation of the desired water-solubleelectrically conductive composition of matter. The polymerizationproceeds effectively at room temperature (25°-30° C.). The temperatureshould not exceed about 30° C. because gelation can occur due to overlyrapid reaction. Thus, lower reaction temperatures are preferred as theypermit greater regulation of the polymerization and enhance watersolubility of the resultant product.

The polymerization is allowed to proceed to completion, following whichthe compositions can be recovered from solution when desired byprecipitation (for instance by adding acetone to the aqueous productsolution). It is preferred then to wash the product to removaloligomeric species and any unconsumed initiator, whereupon thecompositions of matter is filtered and then dried. The resulting powderis readily resoluble in water, preferably deionized water. Typically,5-10 wt. % solutions are effective to permit preparation of spin-coatedthin films.

The invention and its utilization will be illustrated further in thefollowing examples, which are to be construed as illustrative andnon-limiting.

EXAMPLE 1

Polymerization reactions were carried out in aqueous solutionscontaining PSSA, aniline, and ammonium persulfate as theoxidizer/initiator. In one set of experiments, the molarity of the PSSAwas changed while the ratio of PSSA to aniline, and the ratio ofinitiator to aniline, were held constant. The results, set forth inTable 1 below, showed that when the PSSA concentration was greater than0.25M, the polymerization led to a gelled material which was not thedesired product. On the other hand, when the PSSA concentration was0.25M or less, the product of the polymerization was in the form of agreen, clear solution which remained stable even after several days. Thetemperature was about 22° C.

                  TABLE 1                                                         ______________________________________                                        Effect of Polyacid Molarity on Aniline Polymerization                         Molar ratio                                                                             Molar ratio  Molarity of                                            PSSA: aniline                                                                           NH.sub.4 S.sub.2 O.sub.8 : aniline                                                         PSSA       Product                                     ______________________________________                                        1.0       0.25         1.63       green in-                                                                     soluble gel                                 1.0       0.25         1.00       green in-                                                                     soluble gel                                 1.0       0.25         0.50       green in-                                                                     soluble gel                                 1.0       0.25         0.25       green clear                                                                   solution                                    1.0       0.25          0.125     green clear                                                                   solution                                    ______________________________________                                    

EXAMPLE 2

In a second set of experiments, the initial molarity of the PSSAsolution was fixed at 0.25M and the amount of ammonium persulfateinitiator was varied. As shown in Table 2 below, if the ratio ofpersulfate to aniline exceeded 0.25, the polymerization resulted in aninsoluble gel. When the ratio of persulfate to aniline was 0.25 or less,the desired water-soluble complex was obtained. The temperature wasabout 22° C.

                  TABLE 2                                                         ______________________________________                                        Effect of Oxidizing Agent: Aniline Ratio on Aniline                           Polymerization                                                                Molar ratio                                                                             Molar ratio  Molarity of                                            PSSA: aniline                                                                           NH.sub.4 S.sub.2 O.sub.8 : aniline                                                         PSSA       Product                                     ______________________________________                                        1.0       0.125        0.25       green clear                                                                   solution                                    1.0       0.25         0.25       green clear                                                                   solution                                    1.0       0.375        0.25       green in-                                                                     soluble gel                                 1.0       0.05         0.25       green in-                                                                     soluble gel                                 ______________________________________                                    

The water-soluble composition of matter obtained as described in Tables1 and 2 from the green clear solutions were precipitated in acetone,washed several times, filtered and dried to obtain a green powder. Thebulk conductivity of this green powder was on the order of 10⁻² to 10⁻⁴S/cm. The powder was readily soluble in deionized water.

It is a straightforward matter to apply the composition of matterprepared in accordance with the present invention onto a substrate, forinstance by spin coating a 5% aqueous solution at 2,000 rpm onto the topsurface of a baked resist which is superposed on a substrate. Thespin-coated layer is baked, for instance for 2 minutes at 80°-90° C., toevaporate the water and leave behind a discharge layer on the order of150 nm thickness. A discharge layer comprising a composition of matteraccording to the present invention, which has not been cross-linked, isremovable whenever desired by water washing.

When the composition of matter described herein was used as a dischargelayer on a quartz plate in the making of phase-shift masks using anelectron beam resist, no charging was observed during 50 keV exposure.After development, the pattern overlay was found to be similar to thatobtained when a metal based coating was used.

The compositions of matter of the present invention can be used as topsurface electrical discharge layers or as buried electrical dischargelayers for electron beam applications. When the compositions of matterare used as a buried discharge layer, a first resist layer is depositedonto a substrate, a layer of the composition of matter is depositedthereover, and a second resist layer is deposited onto the layer of thecomposition of matter. When the compositions of matter according to thepresent invention are used as a buried discharge layer underneath adielectric resist layer, the top resist layer still charges up. Whenexposed to an electron beam the degree of charging depends upon thethickness of this top layer. If the resist material is not too thick,charge which accumulates on this top surface layer will leak to theconductive interlayer and then to ground if the conductive interlayer isgrounded. It is found that the conductive interlayer does not have to begrounded to avoid a distortion of an incident electron beam. It is onlynecessary that the charge leak away quickly enough so as not to build upany significant potential at the electron beam target point.

The compositions of matter of the present invention have particularusefulness in electron microscopy. Electron microscopy is currently usedin microelectronics to make observations and dimensional measurements ondielectric masks, for example, quartz/chrome masks used in opticallithography. Charging is caused by the incident electron beam. Theconventional resolution to avoid the charging problem is to deposit athin layer of metal onto the mask. This is, however, a destructivemethod since complete removal of the metal layer is quite difficult ifnot impossible. Therefore, scanning electron microscopic observationsand measurements are limited to scrap pieces. Since the compositions ofmatter of the present invention are readily removed, for instance bydissolution in water, they can be used as a discharge layer in scanningelectron microscope application. Since the compositions of matter areremovable, they can also be used as a discharge layer on the surface ofmasks, electronic devices such as semi-conductor chips andsemi-conductor chip packaging substrates which are not scrap pieces.

Alternatively, ring-substituted polymers, such as poly(ortho-ethoxyaniline) and poly(ortho-ethyl aniline), are found to polymerize inassociation with polyacid in a similar manner to form the water-soluble,electrically conductive compositions of matter described herein. Theresulting compositions of matter can be converted to electricallyconductive, water-insoluble products upon irradiation of the compositionof matter. The irradiation, which is believed to cause cross-linking ofthe alkyl groups on the substituents, should be carried out underconditions effective to insolublize the composition of matter. Forinstance, electron-beam and X-ray wavelengths are effective. Wavelengthsin the ultraviolet and/or visible spectrum are also effective, providedthat the compositions of matter including the polymers of the presentinvention have been formulated to include radical initiators such as anazide, an example of which is 4,4'-diazostilbene-2,2'-disulfonic aciddisodium salt.

The preparation of cross-linkable compositions in accordance with thepresent invention is illustrated in the following Examples.

EXAMPLE 3

16.67 g (0.027 moles) of a 30 wt. % aqueous solution of PSSA was dilutedin a flask with water to form a 5 wt. % solution. While the solution wasbeing stirred, 3.69 g (0.027 moles) of distilled ortho-ethoxy anilinewas added slowly to the solution. The solution was then placed in an icebath and cooled to about 0° C. Then, 1.55 g (0.00675 mole) of ammoniumpersulfate was added to the solution. The reaction mixture was allowedto warm to room temperature, where it was held for 4 hours. A greensolution was formed. The resultant composition of matter wasprecipitated from solution by the addition of acetone to the solution.The precipitate was recovered, filtered, washed with additional acetone,and dried, whereupon a green powder was obtained. This powder could beredissolved in water to form a 10 wt. % solution.

EXAMPLE 4

Ortho-ethylaniline and PSSA were reacted in the manner described inExample 3. Again, a green powder was recovered, as a precipitate, whichcould be redissolved in water.

The products of Examples 3 and 4 both exhibited conductivity on theorder of 10^(-S/cm).

The cross-linkable compositions of matter according to the presentinvention can be used to form radiation-curable and/or radiation-curedcoatings on all or part of a substrate. In an advantageous alternative,crosslinkable compositions of matter as described herein can be used toform resist patterns or patterned electrically conductive,water-insoluble layers. After the layer of cross-linkable conductive,soluble material is deposited, the layer is exposed to radiationeffective to cross-link the material. When the radiation is ultraviolet,visible light, or X-ray radiation, a mask is preferably interposedbetween the layer and the radiation source so that radiation impinges onthe layer only where desired, whereby the radiation reaches the layer ina desired pattern of lines and/or shapes that are defined by the maskand/or by movement of the radiation source relative to the substrate. Inthe case of irradiation with electron-beam, a mask is not necessary asthe beam can write directly where desired.

Upon exposure to radiation, the exposed regions of the layer becomewater-insoluble (though still electrically conductive) whereas theunexposed regions remain water-soluble. The unexposed regions can thenbe rinsed with water, thereby leaving behind a desired pattern ofconductive lines. With this "negative resist" technique one can prepareconducting resists for microelectronic applications, such as patterninga dielectric or metal layer on the surface of a semiconductor chip orsemiconductor chip package substrate, or forming circuit patterns.

For instance, films of the compositions of matter prepared in accordancewith Examples 3 and 4 (3000 Å thick) were spun-coated onto an inertsubstrate and baked at 80° C. for 2 minutes and then exposed to electronbeam radiation (at 200 microCoulombs/cm²) in a pattern of lines. Theproduct was then baked at 80° C. for 5 minutes, puddle-developed inwater for 10 seconds and rinsed with isopropanol. A pattern ofconducting lines 0.5 microns wide remained on the substrate.

The compositions of matter prepared in accordance with these examplesand recovered as described therein from the clear green solution did notresult in any significant loss in the quality and resolution ofdeveloped lines when tested for chemical compatibility with variousconventional resist materials.

The compositions of matter of the present invention have additional usessuch as an electromagnetic interference coating on a dielectric surface.For example, electrical components ace frequently contained withindielectric housings such as cabinets, molded plastics and the like. Toreduce the susceptibility of the electronic components contained withinthe housing, the dielectric housings can be coated with the compositionof matter of the present invention. This electromagnetic interferencetechnique is easily implemented in a high volume manufacturing line andhas very low cost.

It is to be understood that the above described embodiments are simplyillustrative of the principles of the invention, and that various othermodifications and changes may be derived by those of skill in the artwhich will embody the principles of the invention and fall within thespirit and scope thereof.

Having thus described the invention, what we claim as new, and desire tosecure by Letters Patent is:
 1. A water-soluble, electrically conductivecomposition of matter capable of forming a stable 5 wt. % solution inwater, comprising a polyacid wherein said polyacid is selected from thegroup consisting of poly(acrylic acid), poly(methacrylic acid),poly(styrene sulfonic acid), poly(vinylsulfonic acid), poly(styreneboric acid), poly(vinyl boric acid), poly(vinyl sulfuric acid),poly(styrene phosphonic acid), poly(vinyl phosphoric acid), poly(styrenephosphonic acid) and poly(vinyl phosphonic acid), and a polymercomprising at least one conjugated region composed of repeating unitswhich contain a conjugated basic atom wherein said polymer is selectedfrom the group consisting of substituted and unsubstituted homopolymersand copolymers of aniline, thiophene, pyrrole, and p-phenylenesulfide,wherein the number of acidic groups in said polyacid exceeds thenumber of protonatable basic atoms in said polymer.
 2. A composition ofmatter according to claim 1 wherein said polyacid is poly(styrenesulfonic acid).
 3. A composition of matter according to claim 1 whereinsaid polyacid is poly(vinyl sulfonic acid).
 4. A composition of matteraccording to claim 1 wherein said polyacid is poly(acrylic acid).
 5. Acomposition of matter according to claim 1 wherein said polyacid ispoly(methacrylic acid).
 6. A composition of matter according to claim 1wherein said polyacid is poly(vinyl phosphonic acid).
 7. A compositionof matter according to claim 1 wherein said polyacid is poly(styrenephosphonic acid).
 8. A composition of matter according to claim 1wherein said polymer is polyaniline.
 9. A composition of matteraccording to claim 8 wherein said polyacid is poly(styrene sulfonicacid).
 10. A composition of matter according to claim 1 wherein saidpolymer is polythiophene.
 11. A composition of matter according to claim1 wherein said polymer is polypyrrole.
 12. A composition of matteraccording to claim 1 wherein said polymer is poly(p-phenylene sulfide).13. A composition of matter according to claim 1 wherein said aniline issubstituted with one or more substituents selected from the groupconsisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30carbon atoms.
 14. A composition of matter according to claim 1 whereinsaid thiophene is substituted with one or more substituents selectedfrom the group consisting of alkyl, alkoxyalkyl, and alkoxy groupscontaining 1 to 30 carbon atoms.
 15. A composition of matter accordingto claim 1 wherein said pyrrole is substituted with one or moresubstituents selected from the group consisting of alkyl, alkoxyalkyl,and alkoxy groups containing 1 to 30 carbon atoms.
 16. A composition ofmatter according to claim 1 wherein said p-phenylene sulfide issubstituted with one or more substituents selected from the groupconsisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30carbon atoms.
 17. A composition of matter according to claim 1 whereinsaid polymer is cross-linkable.
 18. An aqueous solution comprising acomposition of matter according to claim
 1. 19. An aqueous solutionaccording to claim 18 comprising dissolved therein at least about 5 wt.% of said composition of matter.
 20. An aqueous solution according toclaim 18 comprising dissolved therein about 5 wt. % to about 10 wt. % ofsaid composition of matter.
 21. An aqueous solution according to claim18 comprising dissolved therein about 5 wt. % of said composition ofmatter.
 22. A solution according to claim 18 wherein said polyacid ispoly(styrene sulfonic acid).
 23. A solution according to claim 18wherein said polyacid is poly(vinyl sulfonic acid).
 24. A solutionaccording to claim 18 wherein said polyacid is poly(acrylic acid).
 25. Asolution according to claim 18 wherein said polyacid is poly(methacrylicacid).
 26. A solution according to claim 18 wherein said polyacid ispoly(vinyl phosphonic acid).
 27. A solution according to claim 18wherein said polyacid is poly(styrene phosphonic acid).
 28. A solutionaccording to claim 18 wherein said polymer is polyaniline.
 29. Asolution according to claim 18 wherein said polyacid is poly(styrenesulfonic acid).
 30. A solution according to claim 18 wherein saidpolymer is polythiophene.
 31. A solution according to claim 18 whereinsaid polymer is polypyrrole.
 32. A solution according to claim 18wherein said polymer is poly(p-phenylene sulfide).
 33. A solutionaccording to claim 18 wherein said aniline is substituted with one ormore substituents selected from the group consisting of alkyl,alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.
 34. Asolution according to claim 18 wherein said thiophene is substitutedwith one or more substituents selected from the group consisting ofalkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.35. A solution according to claim 18 wherein said pyrrole is substitutedwith one or more substituents selected from the group consisting ofalkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.36. A solution according to claim 18 wherein said p-phenylene sulfide issubstituted with one or more substituents selected from the groupconsisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30carbon atoms.
 37. A solution according to claim 18 wherein said polymeris cross-linkable.
 38. A water-insoluble, electrically conductivecomposition of matter comprising a polyacid selected from the groupconsisting of poly(acrylic acid), (methacrylic acid), poly(styrenesulfonic acid), poly(vinylsulfonic acid), poly(styrene boric acid),poly(vinyl boric acid), poly(vinyl sulfuric acid), poly(styrenephosphoric acid), poly(vinyl phosphoric acid), poly(styrene phosphonicacid) and poly(vinyl phosphonic acid), and a polymer comprising at leastone conjugated region composed of repeating units which contain aconjugated basic atom, wherein said polymer is selected from the groupconsisting of substituted and unsubstituted homopolymers and copolymersof aniline, thiophene, pyrrole, and p-phenylene sulfide,wherein thenumber of acidic groups in said polyacid exceeds the number ofprotonatable basic atoms in said polymer, wherein said composition ofmatter is capable of forming a stable 5 wt. % solution in water whensaid polymer is not cross-linked, wherein said polymer is cross-linked.39. A composition of matter according to claim 38 wherein said polymeris selected from the group consisting of polymers of aniline, thiophene,pyrrole, and p-phenylene sulfide.
 40. A composition of matter accordingto claim 39 wherein said polymer is polyaniline.
 41. A composition ofmatter according to claim 38 wherein said polyacid is poly(styrenesulfonic acid).
 42. A composition of matter according to claim 41wherein said polymer is polyaniline.
 43. A water-soluble, electricallyconductive composition of matter capable of forming a stable 5 wt. %solution in water, and comprising a polyacid and a conjugated polymercomposed of repeating units which contain a conjugated basic atom,wherein the number of acidic groups in said polyacid exceeds the numberof protonatable basic atoms in said polymer, which composition of matteris the product of the process comprising forming an aqueous solution ofone or more monomers selected from the group consisting of substitutedand unsubstituted aniline, thiophene, pyrrole, and mercaptophenol, and apolyacid selected from the group consisting of poly(acrylic acid),poly(methacrylic acid), poly(styrene sulfonic acid), poly(vinylsulfonicacid), poly(styrene boric acid), poly(vinyl boric acid), poly(vinylsulfuric acid), poly(styrene phosphoric acid), poly(vinyl phosphoricacid), poly(styrene phosphonic acid) and poly(vinyl phosphonic acid),wherein the number of acid groups on said polyacid exceeds the number ofsaid basic atoms, and polymerizing the monomer while controlling therate of initiation and the rate of propagation of said polymerizationsuch that the polymerization forms said composition of matter in saidsolution.
 44. A composition of matter according to claim 43 wherein saidpolyacid is poly(styrene sulfonic acid).
 45. A composition of matteraccording to claim 43 wherein said polyacid is poly(vinyl sulfonicacid).
 46. A composition of matter according to claim 43 wherein saidpolyacid is poly(acrylic acid).
 47. A composition of matter according toclaim 43 wherein said polyacid is poly(methacrylic acid).
 48. Acomposition of matter according to claim 43 wherein said polyacid ispoly(vinyl phosphonic acid).
 49. A composition of matter according toclaim 43 wherein said polyacid is poly(styrene phosphonic acid).
 50. Acomposition of matter according to claim 43 wherein said polymer ispolyaniline.
 51. A composition of matter according to claim 43 whereinsaid polyacid is poly(styrene sulfonic acid).
 52. A composition ofmatter according to claim 43 wherein said polymer is polythiophene. 53.A composition of matter according to claim 43 wherein said polymer ispolypyrrole.
 54. A composition of matter according to claim 43 whereinsaid polymer is poly(p-phenylene sulfide).
 55. A composition of matteraccording to claim 43 wherein said aniline is substituted with one ormore substituents selected from the group consisting of alkyl,alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.
 56. Acomposition of matter according to claim 43 wherein said thiophene issubstituted with one or more substituents selected from the groupconsisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30carbon atoms.
 57. A composition of matter according to claim 43 whereinsaid pyrrole is substituted with one or more substituents selected fromthe group consisting of alkyl, alkoxyalkyl, and alkoxy group containing1 to 30 carbon atoms.
 58. A composition of matter according to claim 43wherein said p-phenylene sulfide is substituted with one or moresubstituents selected from the group consisting of alkyl, alkoxyalkyl,and alkoxy groups containing 1 to 30 carbon atoms.
 59. A composition ofmatter according to claim 43 wherein said polymer is cross-linkable.